FOB - is a degrading term for people not up to date on the culture which is an abbreviation for (Fresh Of the Boat.)
meaning you still carry your sense of fashion from your country which clashes with the current countries cultures.

Origin: Hawaii 60's

Local Hawaiians used it to refer to white people who came from mainland US to Hawaii. Its was used a lot by locals and surfers. it was to refer to white people who wasn't up to date on the culture.

It is now used a lot by Asians to refer to immigrant Asians of the same sense.